Compressor

ABSTRACT

A compressor according to the present invention includes an oil separation mechanism and an oil supply mechanism. The oil separation mechanism includes an oil separation chamber and an oil drain path. The oil supply mechanism includes an oil supply port. The oil drain path includes a first flow path formed by penetrating a second partition of a housing and configured to open toward a first partition of a housing from the oil separation chamber, and a second flow path recessed in at least one of the first partition and the second partition and formed by the cooperation of the first partition and the second partition so as to get communicated with the first flow path. An outlet of the second flow path is located at a higher level in a vertical direction than an inlet of the second flow path while avoiding a direction facing the oil supply port.

TECHNICAL FIELD

The present invention relates to a compressor.

BACKGROUND ART

A conventional vane compressor is disclosed in Japanese Patent Laid-Open No. 7-12072. In the compressor, a cylinder block is accommodated in a housing, and a front side plate and a rear side plate are joined and fixed to opposite ends of the cylinder block. An oil storage chamber, which is a discharge chamber, is formed between the rear side plate and the housing. The rear side plate is provided with an oil separator. The oil separator is formed of a casing and an oil separation cylinder fixed to upper part of an oil separation chamber formed in the casing.

In the oil separation chamber, lubricating oil is separated from refrigerant. The refrigerant with the lubricating oil separated therefrom is discharged from a discharge chamber to a refrigerating circuit outside. The lubricating oil in the oil separation chamber is stored in the oil storage chamber via an oil drain path. The lubricating oil in the oil storage chamber is supplied to a vane groove serving as a back pressure chamber, or a sliding portion such as a bearing, through an oil feed passage communicated with the oil storage chamber, where the back pressure chamber produces back pressure to press a vane.

However, with the compressor, in which the oil drain path interconnects the oil separation chamber and the oil storage chamber linearly, flow velocity of the lubricating oil is less prone to fall, and consequently when a large amount of lubricating oil is stored in the oil storage chamber, the lubricating oil in the oil storage chamber tends to be blown or disturbed by the lubricating oil discharged through the oil drain path. Therefore, the refrigerant in the discharge chamber tends to get mixed with the lubricating oil in the oil storage chamber again, and the lubricating oil mixed with the refrigerant tends to be supplied to the vane groove or the bearing through an opening of the oil feed passage. In this case, the sliding portion is not lubricated sufficiently, which raises concerns that noise and vibration may be produced, breaking quiet and that durability may be spoiled.

To resolve these concerns, for example, as described in Japanese Patent Laid-Open No. 2010-31757, it is conceivable to define a space in the casing of the oil separator in the discharge room to store lubricating oil. In this case, it is considered that lubricating oil drained in sequence from the oil drain path and the separated refrigerant gas are less prone to get mixed with each other, which will make it possible to supply lubricating oil not mixed much with refrigerant to the vane groove and the sliding portion and achieve higher quiet and durability.

However, if a space for use to store lubricating oil is provided in the casing of the oil separator as described above, the oil separator will increase in size or become troublesome in producing. If the oil separator increases in size, volume of the discharge chamber will decrease, making discharge pulsation liable to occur, and the entire compressor grows in size, impairing mountability on a vehicle or the like. Also, troublesome producing will result in escalation of production costs.

The present invention has been made in view of the conventional circumstances described above and an object of the invention is to provide a compressor which can be lubricated sufficiently, is less prone to discharge pulsation, and is capable of achieving downsizing and production cost reductions.

SUMMARY OF THE INVENTION

A compressor according to the present invention comprises: a housing; a compression mechanism accommodated in the housing, forming a suction chamber, a discharge chamber, and a compression chamber in conjunction with the housing, and adapted to suck refrigerant into the compression chamber from the suction chamber, compress the refrigerant, and discharge the refrigerant to the discharge chamber; an oil separation mechanism provided in the discharge chamber and adapted to separate lubricating oil from the refrigerant and store the lubricating oil in the discharge chamber; and an oil supply mechanism adapted to lead the lubricating oil in the discharge chamber to the compression mechanism. The housing comprises a housing body provided with an inner circumferential surface extending in a circumferential direction, a first partition provided in the housing body and adapted to separate the compression chamber and the discharge chamber from each other, and a second partition coupled to the first partition and provided with the oil separation mechanism. The oil separation mechanism comprises an oil separation chamber formed in the second partition and adapted to separate the lubricating oil from the refrigerant led from the compression chamber, and an oil drain path adapted to communicate the oil separation chamber with the discharge chamber. The oil supply mechanism comprises an oil supply port formed in the second partition and configured to open vertically downward to take in the lubricating oil from the discharge chamber. The oil drain path comprises a first flow path formed by penetrating the second partition and configured to open toward the first partition from the oil separation chamber and a second flow path recessed in at least one of the first partition and the second partition and formed by the cooperation of the first partition and the second partition so as to get communicated with the first flow path. An outlet of the second flow path is located at a higher level in a vertical direction than an inlet of the second flow path while avoiding a direction facing the oil supply port.

Other aspects and advantages of the invention will be apparent from embodiments disclosed in the attached drawings, illustrations exemplified therein, and the concept of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a vane compressor according to Embodiment 1.

FIG. 2 is a sectional arrow view of the vane compressor according to Embodiment 1, taken in the direction of line II-II in FIG. 1.

FIG. 3 is an expanded sectional view of principal part of the vane compressor of FIG. 1 according to Embodiment 1.

FIG. 4 is a sectional arrow view of the vane compressor according to Embodiment 1, taken in the direction of line IV-IV in FIG. 3.

FIG. 5 is a sectional arrow view of the vane compressor according to Embodiment 1, taken in the direction of line V-V in FIG. 1.

FIG. 6 is a back view of a gasket in the vane compressor according to Embodiment 1.

FIG. 7 is a back view of a cover plate in the vane compressor according to Embodiment 1.

FIG. 8 is a partial sectional view similar to FIG. 4, showing a vane compressor according to Embodiment 2.

FIG. 9 is a partial sectional view similar to FIG. 4, showing a vane compressor according to Embodiment 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Embodiments 1 to 3 which embody the present invention will be described below with reference to the drawings. In the following description, it is assumed that the left side of FIG. 1 corresponds to the front side of the compressor while the right side of FIG. 1 corresponds to the rear side of the compressor. Also, it is assumed that the top side of FIG. 1 corresponds to the top side of the compressor while the bottom side of FIG. 1 corresponds to the bottom side of the compressor. Then, in FIG. 2 and subsequent figures, the front, rear, top, and bottom directions are designated with reference to FIG. 1. The front-and-rear direction and top-and-bottom direction in Embodiments 1 to 3 indicate the directions of a compressor according to the present invention when the compressor is mounted on a vehicle, where the top-and-bottom direction corresponds to a vertical direction, but mounting attitude of the compressor according to the present invention is changed as appropriate depending on the vehicle on which the compressor is mounted, and the front-and-rear direction and top-and-bottom direction in Embodiments 1 to 3 are exemplary and not restrictive.

Embodiment 1

An electric vane compressor (hereinafter referred to simply as a “compressor”) according to Embodiment 1 shown in FIG. 1 is an example of a concrete form of the compressor according to the present invention. The compressor includes a housing 1, a motor mechanism 3, a compression mechanism 5, an oil separation mechanism 7, and an oil supply mechanism 9. The motor mechanism 3 drives the compression mechanism 5 by being accommodated in the housing 1. By being accommodated in the housing 1, the compression mechanism 5 forms a suction chamber 11, a discharge chamber 13, and compression chambers 15 in conjunction with the housing 1. Then, the compression mechanism 5 sucks refrigerant from the suction chamber 11 into the compression chambers 15, compresses the refrigerant and discharges the compressed refrigerant to the discharge chamber 13. Being installed in the discharge chamber 13, the oil separation mechanism 7 separates lubricating oil from the refrigerant and stores the separated lubricating oil in the discharge chamber 13. The oil supply mechanism 9 leads the lubricating oil in the discharge chamber 13 to the compression mechanism 5.

Specifically, the housing 1 includes a motor housing 17, a gasket 43, a compressor housing 19, a first side plate 21, a cylinder block 23, a second side plate 25, a gasket 59, and a cover plate 27. The compressor housing 19 corresponds to a housing body according to the present invention, the second side plate 25 and the gasket 59 correspond to a first partition according to the present invention, and the cover plate 27 corresponds to the second partition according to the present invention.

A cylindrical circumferential wall 17 a of the motor housing 17 extends in an axial direction from a front end side to a rear end side. The circumferential wall 17 a is closed on the front end side by a front wall 17 b and provided with an opening 17 c on the rear end side. The suction chamber 11 serving also as a motor chamber is formed inside the motor housing 17. An inlet port 17 d communicated with the suction chamber 11 is formed in the circumferential wall 17 a. A bearing 29 is provided on the front wall 17 b and a rotating shaft 31 is installed in the bearing 29 rotatably around a rotational axis X1. The inlet port 17 d is connected with an evaporator via a non-illustrated pipe. The compressor, a condenser, an expansion valve, and the evaporator form an air-conditioning apparatus of the vehicle. The refrigerant passing through the evaporator is sucked into the suction chamber 11 through the inlet port 17 d.

A stator 33 is fixed to an inner side of the circumferential wall 17 a of the motor housing 17, and a motor rotor 35 is fixed to the rotating shaft 31. The motor rotor 35 is placed in the stator 33. A connection terminal 37 is fixed to the front wall 17 b, and the connection terminal 37 is provided with lead wires 39 extending to the stator 33 in the suction chamber 11 from outside. The lead wires 39 are provided with a cluster block 41 within the circumferential wall 17 a. The stator 33, the motor rotor 35, the connection terminal 37, the lead wires 39, and the cluster block 41 form the motor mechanism 3.

The compressor housing 19 is fixed to a rear end of the motor housing 17 by plural non-illustrated bolts. A circumferential wall 19 a in a cylindrical shape extends in the axial direction from a front end side to a rear end side of the compressor housing 19. The circumferential wall 19 a is closed on a rear end side by a rear wall 19 b and provided with an opening on the front end side. The circumferential wall 19 a has an inner circumferential surface 19 d extending in a circumferential direction. The inner circumferential surface 19 d is coaxial with the rotational axis X1.

An opening 19 c of the compressor housing 19 is coupled to the opening 17 c of the motor housing 17, closing both the motor housing 17 and the compressor housing 19. The gasket 43 is provided between the opening 17 c of the motor housing 17 and the opening 19 c of the compressor housing 19. Also, the first side plate 21 is fixed to the compressor housing 19 together with the motor housing 17 on the side of the opening 19 c. The first side plate 21 defines the suction chamber 11 between the motor housing 17 and the cylinder block 23 by extending in a radial direction, and separates the compression chamber 15 and the suction chamber 11 from each other. An O-ring 45 is provided between the first side plate 21 and the compressor housing 19. A shaft hole 21 a is formed in the first side plate 21 coaxially with the bearing 29. The rotating shaft 31 is passed through the shaft hole 21 a.

The cylinder block 23, the second sideplate 25, and the cover plate 27 are accommodated in the compressor housing 19. The cylinder block 23 and the second side plate 25 are assembled on a rear face of the first side plate 21 by plural bolts 47 as shown in FIG. 2. The cylinder block 23 is sandwiched from front and rear by the first side plate 21 and the second side plate 25 as shown in FIG. 1. The second side plate 25 is fitted in the inner circumferential surface 19 d of the compressor housing 19. An O-ring 48 is provided between the second side plate 25 and the inner circumferential surface 19 d. A shaft hole 25 a is formed in the second side plate 25 coaxially with the bearing 29 and the shaft hole 21 a. The rotating shaft 31 is passed also through the shaft hole 25 a.

A cylinder chamber 23 a is formed in the cylinder block 23 as shown in FIG. 2. The cylinder chamber 23 a is closed by the rear face of the first side plate 21 and a front face of the second side plate 25 as shown in FIG. 1. A rotor 49 is fixed integrally to the rotating shaft 31 between the first side plate 21 and the second side plate 25. The rotor 49 is configured to be rotatable around the rotational axis X1 in the cylinder chamber 23 a. Plural vane grooves 49 a are formed in the rotor 49 as shown in FIG. 2. Vanes 51 are installed advanceably/retractably in the respective vane grooves 49 a.

Also, a suction passage 23 b and a suction port 23 c are formed in the cylinder block 23. The suction passage 23 b extends in the front-and-rear direction parallel to the rotational axis X1. The suction passage 23 b is communicated with the cylinder chamber 23 a through the suction port 23 c. Furthermore, a discharge space 23 d is formed in the cylinder block 23 in conjunction with the inner circumferential surface 19 d of the compressor housing 19. The discharge space 23 d is communicated with the cylinder chamber 23 a through a discharge port 23 e. A discharge reed valve 53 adapted to open and close the discharge port 23 e and a discharge retainer 55 adapted to restrict an opening degree of the discharge reed valve 53 are provided in the discharge space 23 d. The discharge reed valve 53 and the discharge retainer 55 are fixed to the cylinder block 23 by a bolt 57.

As shown in FIG. 1, a suction passage 21 c adapted to communicate the suction chamber 11 and the suction passage 23 b with each other is formed by penetrating the first side plate 21. The gasket 59 is provided between the second side plate 25 and the cover plate 27. The second side plate 25, gasket 59, and the cover plate 27 are assembled and fixed by plural bolts 76 as shown in FIGS. 3 to 5. The second side plate 25, gasket 59, and the cover plate 27 form the discharge chamber 13 between the cylinder block 23 and the compressor housing 19 by extending in the radial direction and separates the compression chamber 15 and the discharge chamber 13 from each other.

An introduction passage 25 b adapted to communicate the discharge space 23 d with an oil separation chamber 65 described later is formed by penetrating the second side plate 25, gasket 59, and the cover plate 27. The first side plate 21, the cylinder block 23, the second side plate 25, the rotor 49, the vanes 51, the discharge reed valve 53, the discharge retainer 55, and the bolt 57 form the compression mechanism 5. The compression mechanism 5 forms the compression chamber 15 defined by the front face of the cylinder chamber 23 a, an inner circumferential surface of the cylinder chamber 23 a, the rear face of the cylinder chamber 23 a, the outer circumferential surface of the rotor 49, and the vanes 51. Aback pressure chamber 61 is provided between each vane groove 49 a and the corresponding vane 51.

As shown in FIG. 5, the second side plate 25 and the cover plate 27 are coupled together in an annular coupling region 73 via the gasket 59. An intermediate pressure chamber 69 is formed between the second side plate 25 and the cover plate 27, being located closer to the side of the rotational axis X1 than to the coupling region 73 is. As shown in FIGS. 3 and 4, the intermediate pressure chamber 69 makes part of the second side plate 25 and part of the cover plate 27 spaced away from each other in a direction of the rotational axis X1. When viewed in the direction of the rotational axis X1, the intermediate pressure chamber 69 is placed so as to overlap at least part of the rear face of the cylinder chamber 23 a.

As shown in FIGS. 3 to 5, the oil separation mechanism 7 is provided on the cover plate 27. The oil separation mechanism 7 includes a cylindrical member 63, the oil separation chamber 65, and an oil drain path 71. As shown in FIG. 3, the oil separation chamber 65 includes an upper chamber 65 a scooped out in a columnar manner and a lower chamber 65 b communicated with the upper chamber 65 a on an underside of the upper chamber 65 a, scooped out in a columnar manner coaxially with the upper chamber 65 a, and configured to be a little smaller in diameter than the upper chamber 65 a. As shown in FIG. 5, the upper chamber 65 a and the lower chamber 65 b are formed with upper part inclined slightly inward with respect to a top-and-bottom direction slightly on the left side of the cover plate 27 in FIG. 5.

The cylindrical member 63 cylindrical in shape is fixed to an upper end of the upper chamber 65 a. As shown in FIG. 3, the cylindrical member 63 is formed of a large diameter portion 63 a and a small diameter portion 63 b, where the large diameter portion 63 a is configured to be large in diameter and press-fitted in the upper chamber 65 a while the small diameter portion 63 b is formed integrally and coaxially with the large diameter portion 63 a under the large diameter portion 63 a and configured to be a little smaller in diameter than the large diameter portion 63 a. The refrigerant led to the oil separation chamber 65 from the discharge space 23 d through the introduction passage 25 b circles in an annular space formed by the small diameter portion 63 b and an inner circumferential surface of the upper chamber 65 a. Consequently, a centrifugal force acts on the refrigerant, causing the lubricating oil contained in the refrigerant to separate, drip off the inner circumferential surface of the upper chamber 65 a, and move to the lower chamber 65 b.

As shown in FIG. 1, an outlet port 19 e is formed in the circumferential wall 19 a of the compressor housing 19. The outlet port 19 e is connected with a condenser via a non-illustrated pipe. The refrigerant with lubricating oil separated therefrom in the oil separation chamber 65 is discharged to the condenser through the outlet port 19 e.

As shown in FIG. 4, a through-hole 71 a is formed in the cover plate 27, at a lower end of the lower chamber 65 b, extending, at right angles, to an end face of the gasket 59, which is the coupling region 73. The through-hole 71 a extends in a tangential direction from a direction in which the refrigerant circles in the lower chamber 65 b. As shown in FIG. 6, the gasket 59 has a flat end face configured to come face-to-face to the through-hole 71 a of the cover plate 27. The through-hole 71 a is a first flow path. Also, as shown in FIGS. 4 and 7, a linear groove 71 c is recessed, in the cover plate 27, being communicated with the through-hole 71 a and extending linearly to an outer circumferential side. The linear groove 71 c is a recessed portion. Surfaces are joined together such that an end face of the cover plate 27 with the linear groove 71 c formed therein and an end face of the gasket 59 will face each other, and the linear groove 71 c makes up a second flow path according to the present invention.

One end of the linear groove 71 c is an inlet 71 b communicated with the through-hole 71 a, and another end is an outlet 71 d opening to the discharge chamber 13. As shown in FIG. 7, the outlet 71 d is located at a higher level in the vertical direction than the inlet 71 b. That is, the linear groove 71 c extends, being inclined at an angle of θ° with respect to a horizontal direction when the compressor is mounted on the vehicle. Consequently, as shown in FIG. 5, the linear groove 71 c extends in a direction away from an oil supply port 75 c described later. Also, as shown in FIGS. 4 and 5, the outlet 71 d of the linear groove 71 c is placed face-to-face with the inner circumferential surface 19 d of the compressor housing 19, being spaced away only by about a few millimeters. More specifically, as shown in FIG. 5, if a normal L is defined at a position where the outlet 71 d comes face-to-face with the inner circumferential surface 19 d, the linear groove 71 c intersects the normal L at an acute angle. The through-hole 71 a and the linear groove 71 c form the oil drain path 71.

Also, first and second oil flow paths 75 a and 75 b are formed in the cover plate 27. The first oil flow path 75 a is communicated with a bottom of the discharge chamber 13 through the oil supply port 75 c at a lower end, and extends upward, approaching the rotational axis X1. The second oil flow path 75 b extends to the intermediate pressure chamber 69 while being continuous with the upper end of the first oil flow path 75 a. Consequently, the lubricating oil in the discharge chamber 13 is taken into the first and second oil flow paths 75 a and 75 b through the oil supply port 75 c, and led to the intermediate pressure chamber 69. In so doing, the first and second oil flow paths 75 a and 75 b function as throttle channels and leads the lubricating oil to the intermediate pressure chamber 69 such that pressure in the intermediate pressure chamber 69 will be lower than in the discharge chamber 13, but higher than in the suction chamber 11.

As shown in FIGS. 1 and 3, a communicating path 77 adapted to communicate the intermediate pressure chamber 69 and the back pressure chamber 61 with each other is formed by penetrating the second side plate 25. Also, an oil groove 25 c annular in shape and coaxial with the rotational axis X1 is formed in the second side plate 25. Furthermore, as shown in FIG. 1, an oil groove 21 b annular in shape and coaxial with the rotational axis X1 is formed in the first side plate 21. The oil grooves 21 b and 25 c are communicated with a bottom of each vane groove 49 a regardless of rotation of the rotor 49. The oil supply port 75 c, the first and second oil flow paths 75 a and 75 b, the intermediate pressure chamber 69, the communicating path 77, and the oil groove 25 c make up a back pressure flow path. The oil supply port 75 c, the first and second oil flow paths 75 a and 75 b, the intermediate pressure chamber 69, the communicating path 77, the oil groove 25 c, the back pressure chamber 61, and the oil groove 21 b make up the oil supply mechanism 9.

In the compressor, when electric power is supplied to the stator 33 shown in FIG. 1, the motor mechanism 3 operates, causing the rotating shaft 31 to rotate around the rotational axis X1. Consequently, the compression mechanism 5 operates and the rotor 49 rotates in the cylinder chamber 23 a. In doing so, in the cylinder chamber 23 a, the vanes 51 advance and retract into/from the respective vane grooves 49 a along with the rotation of the rotor 49. Consequently, the refrigerant in the suction chamber 11 is sucked into the compression chamber 15, compressed in the compression chamber 15, and discharged to the discharge chamber 13.

In doing so, the lubricating oil is separated from the refrigerant in the oil separation chamber 65 of the oil separation mechanism 7. The refrigerant from which the lubricating oil has been separated is supplied to the condenser outside through the discharge chamber 13 and the outlet port 19 e. The lubricating oil in the oil separation chamber 65 is stored in lower part of the discharge chamber 13 by passing through the oil drain path 71.

Meanwhile, in the compressor, the second side plate 25 and the cover plate 27 remain coupled together in the coupling region 73, and the oil drain path 71 is formed of the through-hole 71 a and the linear groove 71 c. The through-hole 71 a is formed by penetrating the cover plate 27 and extends from the lower chamber 65 b of the oil separation chamber 65 to the end face of the gasket 59, which is the coupling region 73. Consequently, the lubricating oil discharged in sequence from the lower chamber 65 b of the oil separation chamber collides with the end face of the gasket 59 first of all, thereby having its flow direction changed and having its force weakened.

Also, the linear groove 71 c is recessed in the coupling region 73 of the cover plate 27. The outlet 71 d of the linear groove 71 c is located at a higher level in the vertical direction than the inlet 71 b. Consequently, the linear groove 71 c is communicated with the through-hole 71 a and extends such that the outlet 71 d opens in a direction different from a direction toward the oil supply port 75 c. The lubricating oil discharged from the linear groove 71 c in sequence is discharged into the discharge chamber 13 in such a way as to move away from the oil supply port 75 c. With the present compressor, in particular, because the outlet 71 d of the linear groove 71 c is placed face-to-face with the inner circumferential surface 19 d of the compressor housing 19, the lubricating oil discharged in sequence from the linear groove 71 c collides also with the inner circumferential surface 19 d. That is, the lubricating oil flowing through the oil drain path 71 has its flow changed by passing through a bent path before being stored in the discharge chamber 13 and has its flow weakened by colliding with wall surfaces at least twice. Also, since the linear groove 71 c intersects the normal L at an acute angle, the lubricating oil discharged in sequence from the linear groove 71 c is guided along the inner circumferential surface 19 d.

Consequently, with the present compressor, even when a large amount of lubricating oil is stored in the discharge chamber 13, the lubricating oil discharged in sequence from the oil separation chamber 65 is less prone to blow or disturb the lubricating oil in the discharge chamber 13. This makes the refrigerant in the discharge chamber 13 less prone to get mixed with the lubricating oil in the discharge chamber 13 again. In particular, since the outlet 71 d of the linear groove 71 c is not directed toward the oil supply port 75 c, the lubricating oil discharged from the outlet 71 d is kept from disturbing the refrigerant gas and the lubricating oil around the oil supply port 75 c. Consequently, the lubricating oil just as stored in the discharge chamber 13 almost without being mixed with refrigerant tends to be supplied to the compression mechanism 5 through the oil supply port 75 c. Specifically, the lubricating oil taken in through the oil supply port 75 c reaches the intermediate pressure chamber 69 through the first and second oil flow paths 75 a and 75 b, and is supplied from the intermediate pressure chamber 69 to the back pressure chambers 61 through the oil groove 25 c and the communicating path 77. The lubricating oil in the back pressure chambers 61 lubricates the sliding portions between the respective vane grooves 49 a and vanes 51 as well as sliding portions between the respective vanes 51 and the cylinder chamber 23 a. Also, the lubricating oil in the back pressure chambers 61 lubricates the shaft holes 21 a and 25 a by passing through the oil grooves 21 b and 25 c. In this way, the present compressor allows the compression mechanism 5 to be lubricated sufficiently. Thus, the compressor is less prone to noise and vibration, and exhibits high durability as well as high quiet. Also, compared to when refrigerant gas is mixed in, each vane 51 can be pressed stably by hydraulic pressure, making it possible to prevent chattering of the vane 51 and improve the quiet of the compressor.

Also, in the present compressor, since an end face of the cover plate 27 provided with the linear groove 71 c and an end face of the gasket 59 are placed facing each other and the second flow path is formed by joining together the end faces, the cover plate 27 does not increase in size and is easy to produce. Thus, the compressor makes it easy to prevent discharge pulsation by allowing the discharge chamber 13 to have a large volume and makes it possible to downsize the entire compressor and achieve a high mountability on a vehicle or the like. Also, the compressor, which is easy to produce, can reduce production costs.

Thus, the compressor can be lubricated sufficiently, is less prone to discharge pulsation, and is capable of achieving downsizing and production cost reductions.

Embodiment 2

In the compressor according to Embodiment 2, the cover plate 27 has a flat end face on an outer circumferential side of the through-hole 71 a as shown in FIG. 8. Also, a through-hole 71 e matching the through-hole 71 a in the cover plate 27 is formed by penetrating the gasket 59. A linear groove 71 f linear in shape is formed in the second side plate 25 by being communicated with the through-holes 71 a and 71 e. Surfaces are joined together such that the end face of the gasket 59 with the through-hole 71 e formed therein and an end face of the second side plate 25 with the linear groove 71 f formed therein will face each other. The through-hole 71 e and the linear groove 71 f make up the second flow path according to the present invention. The through-hole 71 a, the through-hole 71 e, and the linear groove 71 c make up the oil drain path 71.

The rest of the configuration is similar to Embodiment 1. The present compressor achieves functions and effects similar to those of Embodiment 1.

Embodiment 3

In the compressor according to Embodiment 3, the cover plate 27 has a flat end face on an outer circumferential side of the through-hole 71 a as shown in FIG. 9. Besides, the second sideplate 25 also has a flat end face on an outer circumferential side. A linear notch 71 g is formed in the gasket 59, being communicated with the through-hole 71 a in the cover plate 27. Surfaces are joined together such that an end face of the cover plate 27 and an end face of the second side plate 25 will face two end faces, respectively, of the gasket 59 in which the notch 71 g is formed. The notch 71 g corresponds to the second flow path according to the present invention. The through-hole 71 a and the notch 71 g make up the oil drain path 71.

The rest of the configuration is similar to Embodiment 1. The present compressor also achieves functions and effects similar to those of Embodiment 1.

Although the present invention has been described above in line with Embodiments 1 to 3, it is needless to say that the invention is not limited to the above-described embodiments 1 to 3, but may be appropriately modified in application without departing from the gist of the invention.

For example, whereas the second flow path is formed into a linear shape from the linear groove 71 c, the linear groove 71 f, or the notch 71 g linear in shape in Embodiments 1 to 3, the second flow path may be formed into a bent or curved shape.

Also, whereas three vanes are provided in the compressors according to Embodiments 1 to 3, the number of vanes is not limited to three, and may be, for example, two or four.

Also, whereas the present invention is embodied as a vane compressor in Embodiments 1 to 3, the present invention can also be embodied as a scroll compressor or the like. 

1. A compressor comprising: a housing; a compression mechanism accommodated in the housing, forming a suction chamber, a discharge chamber, and a compression chamber in conjunction with the housing, and adapted to suck refrigerant into the compression chamber from the suction chamber, compress the refrigerant, and discharge the refrigerant to the discharge chamber; an oil separation mechanism provided in the discharge chamber and adapted to separate lubricating oil from the refrigerant and store the lubricating oil in the discharge chamber; and an oil supply mechanism adapted to lead the lubricating oil in the discharge chamber to the compression mechanism, wherein the housing comprises a housing body provided with an inner circumferential surface extending in a circumferential direction, a first partition provided in the housing body and adapted to separate the compression chamber and the discharge chamber from each other, and a second partition coupled to the first partition and provided with the oil separation mechanism, the oil separation mechanism comprises an oil separation chamber formed in the second partition and adapted to separate the lubricating oil from the refrigerant led from the compression chamber, and an oil drain path adapted to communicate the oil separation chamber with the discharge chamber, the oil supply mechanism comprises an oil supply port formed in the second partition and configured to open vertically downward to take in the lubricating oil from the discharge chamber, the oil drain path comprises a first flow path formed by penetrating the second partition and configured to open toward the first partition from the oil separation chamber and a second flow path recessed in at least one of the first partition and the second partition and formed by the cooperation of the first partition and the second partition so as to be communicated with the first flow path, and an outlet of the second flow path is located at a higher level in a vertical direction than an inlet of the second flow path while avoiding a direction facing the oil supply port.
 2. The compressor according to claim 1, wherein the outlet of the second flow path is placed face-to-face with the inner circumferential surface of the housing body.
 3. The compressor according to claim 1, wherein if a normal is defined at a position where the outlet of the second flow path comes face-to-face with the inner circumferential surface of the housing body, the second flow path intersects the normal at an acute angle.
 4. The compressor according to claim 1, wherein: the housing comprises a cylinder block in which a cylinder chamber is formed, the housing body configured to surround the cylinder block, the first partition configured to form the discharge chamber between the cylinder block and the housing body, and the second partition; the compression mechanism comprises a rotor installed in the cylinder chamber rotatably around a rotational axis with a plurality of vane grooves formed therein and vanes installed advanceably/retractably in the respective vane grooves; the compression mechanism forms the compression chamber defined by one face of the cylinder chamber, an inner circumferential surface of the cylinder chamber, another face of the cylinder chamber, an outer circumferential surface of the rotor, and the respective vanes; a back pressure chamber is provided between each of the vanes and the corresponding one of the vane grooves; and the oil supply port is communicated with the back pressure chambers through a back pressure flow path.
 5. The compressor according to claim 4, wherein the first partition includes a side plate configured to form one face of the cylinder chamber.
 6. The compressor according to claim 4, wherein the first partition includes a gasket. 